Browsing by Subject "Small intestine"
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- PublicationEmbargoEffects of dietary polyamines at physiologic doses in early-weaned piglets(Elsevier, 2009-01-22) Sabater Molina, María; Larqué, Elvira; Torrella, Francisco; Plaza, Javier; Muñoz, Antonio; Zamora, Salvador; Lozano Parejo, Teresa; Ciencias SociosanitariasObjective: Polyamines are essential for many cell functions, and they form part of the composition of maternal milk; despite this, their addition to infant formulas is currently under evaluation. The aim of the present study was to evaluate the effects of milk formulas designed to resemble sow milk supplemented with polyamines at maternal physiologic milk doses on the gut maturation of early-weaned piglets. Methods: We fed 30 newborn piglets with maternal milk (n=10), a control milk formula (n=10), or a milk formula supplemented with polyamines (5 nmol/mL of spermine and 20 nmol/mL of spermidine, n=10) for 13 d (day 2 after birth through day 15). Several growth and intestinal development parameters were measured. Results: The piglets fed the formula containing polyamine at physiologic doses showed significantly increased crypt depth in the small intestine compared with those fed with the control formula. Villus length was correlated to crypt depth. Although there were no differences in the disaccharidase activities between the animals fed the two formulas, alkaline phosphatase and gamma-glutamyl transferase activities tended to be higher in the jejunum of those fed the polyamine-supplemented diet. Dietary polyamines did not significantly modify the gut mucosal concentrations of putrescine, spermine, or spermidine. Conclusion: Milk formulas supplemented with polyamines at maternal milk physiologic doses slightly enhanced gut growth and maturation in neonatal piglets.
- PublicationOpen AccessEffects of experimental diabetes in the noradrenergic and cholinergic nerves of the rat small intestine(Murcia: F. Hernández, 1990) Cuervas-Mons, M.; Morte, L.; Junquera, C.; Ramón y Cajal, S.An histochemical research on cholinergic and noradrenergic fibres of the adventitia layer and of the myenteric plexus of the terminal ileum from rats with streptozotocin-induced diabetes, after 20 weeks of evolution of the illness, was carried out to study changes in the innervation of the gut. The cholinergic nerves, revealed through their acetylcholinesterase activity, did not present alterations, but an evident reduction in number of the noradrenergic nerves and swollen intensely fluorescent varicosities, were observed, both in the perivascular and myenteric plexus of terminal ileum from diabetic animals.
- PublicationOpen AccessEpithelia1 integrity, cell death and cell loss in mammalian small intestine(Murcia : F. Hernández, 1999) Mayhew, T.M.; Myklebust, R.; Whybrow, A.; Jenkins, R.In recent years, the different mechanisms of epithelial cell loss which occur in mammalian and avian small intestine have been re-investigated. Information is now available for a variety of mammalian types and mechanisms can be divided into two major classes: [i] those preserving epithelial integrity by maintaining intercellular tight junctions throughout early-to-late stages of cell extrusion; and [ii] those which compromise integrity by introducing breaches in epithelial continuity. Both classes are associated with the activity andtor proximity of non-epithelia1 cells (mainly lymphocytes and mononuclear phagocytes) located in the epithelium or underlying lamina propria. Intraepithelial lymphocytes may be involved in enterocyte targetting and killing whilst lamina propria (LP) macrophages sequester cell debris. Where epithelial integrity is maintained, two types of loss can be identified. In the first (type l), complete cells are extruded into the lumen. In the second (type 2), only anucleate apical cell fragments pass into the lumen . There are two variants of type 2 loss distinguishable by the fate of the nucleated basal portions of cells. One variant (type 2a) creates large intercellular spaces extending from the preserved apical cap to the basal lamina and containing enterocyte debris for phagocytosis. The second (type 2b) involves the gradual shrinkage of individual cells (which become more electron-dense) and in situ degeneration of their nucleated subapical portions in increasingly narrower intercellular spaces between adjacent healthy enterocytes. The mechanism of removal of these fragments is unclear but may be via macrophages or surrounding enterocytes. Apoptosis has been implicated in both type 1 and type 2 extrusion. In contrast, type 3 loss involves morphological changes in enterocytes which are reminiscent of those seen in necrosis and is accompanied by breaks in epithelial continuity following cell swelling, a decrease in cell electron density and total or subtotal degradation of organelles and membranes. It ends in loss of either an abnormal cell apex (with subsequent exposure of the degraded cell contents and their spillage into the lumen) or a complete cell remnant (extruded into the lumen before total disintegration of plasma membranes).
- PublicationOpen AccessMacrophages in the external muscle layers of mammalian intestines(Murcia : F. Hernández, 1995) Mikkelsen, H.B.The literature on macrophages in the muscularis extema of mouse, rat, guinea pig, cat, dog and human gut is reviewed. In smaller mammals macrophages are regularly situated in two locations: in the serosa and at the level of Auerbach's plexus between the longitudinal and circular muscle layers. In addition a few solitary cells are present at the level of the deep muscular plexus. At the level of Auerbach's plexus the macrophages occur as a constant and regularly distributed cell population with intimate associations between macrophages and interstitial cells of Cajal. Morphologically they differ from most resident macrophages in being irregular in shape with 4-6 primary cytoplasmic processes, which branch and give a stellate appearance. They have been demonstrated with endocytotic markers (trypan red, FWC-dextran, cholera toxin), immunocytochemically with macrophage antibodies (F4180, M1170) and antibodies against MHC class-I1 antigen, GABA and cGMP. In muscularis externa of the human gut a regularly distributed cell population of macrophages is not obvious. However, a phenotypically distinct subgroup is identified by light microscopy with the pan macrophage antibodies (EBM11, C3bl and partly by ~1 5 0 . 9 5a)n~d shows MHC class-I1 antigen. By electron microscopy muscularis extema macrophages, in all species investigated, appear to be endocytically downregulated, and since they are lysozyme, prostaglandine H synthase (both constitutive and activated) and acid phosphatase negative, they appear to be inactivated cells. Both origin and function of these cells are unknown. They may be immunocompetent, participate in a neuroimmune axis, tissue growth and modulation or other regulations of specific cell functions.
- PublicationOpen AccessQuantification of eosinophil densities in the oesophagus, stomach and small bowel of adults: A review of endoscopic and surgical specimens with normal histology, Free State Province, South Africa(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2024) Budding, Liska; Duncan, Jane; Joubert, Gina; Goedhals, JacquelineAim. Studies defining eosinophil densities in the gastrointestinal tract (GIT) are limited. To assess whether eosinophils are pathologically infiltrating the GIT, it is important to evaluate eosinophil densities for specific populations. Methods. A retrospective, quantitative, comparative study was conducted to determine the number of eosinophils in the oesophagus, stomach and small bowel of patients in central South Africa and to investigate whether a statistically significant difference occurred between ethnic and gender groups. Results. In total, 309 histological sections from the oesophagus, gastric corpus, gastric antrum and small intestine were sampled from male and female, African and Caucasian patients. Histology reports and review of the slides confirmed the absence of histological abnormality. The number of eosinophils in the epithelium and lamina propria were manually quantified. The eosinophil values across gender, ethnicity and location were 0-2.0/mm2 for the oesophagus, 0-53.0/mm2 for the gastric corpus and 7.1-115.3/mm2 for the small intestine. Regarding the gastric antrum, African and Caucasian females had eosinophil values of 1.0-35.7/mm2 and 0-22.4/mm2, respectively. Males had an eosinophil density of 0-31.6/mm2 in the gastric antrum. The eosinophil values in the oesophagus, gastric corpus and small bowel were not significantly different between genders and ethnic groups. The only site where ethnicity influenced the number of eosinophils was the gastric antrum, a discrepancy that cannot be explained. Conclusion. To the authors' knowledge, this is the first report on the eosinophil densities in the oesophagus, stomach and small bowel of adults in South Africa.
- PublicationOpen AccessRegional variation in ontogeny of class II antigens in enterocytes of mouse small intestine(Murcia : F. Hernández, 1992) Sidhu, Nirmal K.; Wrightk, Glenda M.; Markham, R.J. Fred; Singh, AmreekThe ontogeny of major histocompatibility class I1 antigens in small intestine enterocytes of postnatal C3HlHe mice was investigated. Cryosections of duodenal, jejunal, and ileal segments from 7-, 14-, 16-, 20-, 21-, 23-, 25-, 27-, 28-day-old and 7-week-old mice were stained for the class I1 antigens with MRC OX6 monoclonal antibodies by peroxidase-antiperoxidase labelling. In adults, the duodenum exhibited least expression of class I1 antigens that increased progressively towards the ileum. The expression in the villous epithelium was first seen in the duodenum and jejunum 21 days after birth but the ileal enterocytes did not exhibit any class I1 antigens. The earliest appearance (21 days postnatal) of class 11 antigens in the enterocytes coincides with the age of weaning which suggests that immunologic stimulation by ingested antigens after weaning may influence expression of these antigens. At day 28 after birth, the duodenum and jejunum expressed levels comparable to those in the adults. The first expression of the antigens seen in the ileum was at day 28 postpartum. Crypt epithelium of the three regions of the small intestine showed expression similar to that of corresponding regional villous enterocytes. We conclude that there is an age-dependent regional variation in the expression of class I1 antigens in enterocytes, and the expression increases with age. The variation in expression of the class I1 antigens in enterocytes of postnatal mice is attributed to the developmental status of the tissue. The nature of postnatal expression of the antigens is important since an early appearance of these antigens may have implications in autoimmunity.